Jellyfish degradation in a shallow coastal Mediterranean lagoon

Recurrent jellyfish blooms in the coastal zone call for understanding impacts of jelly-falls on functioning benthic communities, especially shallow enclosed ecosystems where their biomass can affect local carbon cycling and productivity. Each year, Aurelia coerulea appear collapse a semi-enclosed Mediterranean lagoon (the Thau lagoon, south France). Although is shallow, large accumulations dead are never observed its bottom, so it was hypothesized that decaying were rapidly consumed by macrobenthic organisms. The current work aimed to test this hypothesis, estimating impact presence A. aurelia medusae community composition assessing loss rates under different scenarios accessibility macrobenthos. Unexpectedly, our results revealed limited role scavengers disappearance medusae, although later particularly fast (19–78h). Only one taxon (Tritia sp., Nassariidae family) showed significant response seabed. Thus, suggest from rapid degradation consumption microorganisms, likely due combined effects high temperatures small size medusae. important produced during might essentially boost microbial food web. potential controlling biogeochemical cycles web lagoons discussed, underlying need include process ecosystem-based models.